using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;

namespace Pong_Project
{
    /// <summary>
    /// This is the main type for your game
    /// </summary>
    public class Game : Microsoft.Xna.Framework.Game
    {
        GraphicsDeviceManager graphics;
        SpriteBatch spriteBatch;
        ViewManager viewManager;

        private static Vector2 windowSize = new Vector2(735, 490);
        private static readonly Game game = new Game();
        private static readonly Random random = new Random();

        private Game()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
        }

        public static Game GetInstance()
        {
            return game;
        }

        public static Random Random
        {
            get { return random; }
        }

        public static float WindowHeight
        {
            get { return windowSize.Y; }
            set { windowSize.Y = value; }
        }

        public static float WindowWidth
        {
            get { return windowSize.X; }
            set { windowSize.X = value; }
        }

        /// <summary>
        /// Allows the game to perform any initialization it needs to before starting to run.
        /// This is where it can query for any required services and load any non-graphic
        /// related content.  Calling base.Initialize will enumerate through any components
        /// and initialize them as well.
        /// </summary>
        protected override void Initialize()
        {
            // Sets the game fps to 60
            base.IsFixedTimeStep = true;
            base.TargetElapsedTime = new TimeSpan((long)(TimeSpan.TicksPerSecond / 60f));

            graphics.PreferredBackBufferHeight = (int)WindowHeight;
            graphics.PreferredBackBufferWidth = (int)WindowWidth;
            graphics.ApplyChanges();

            viewManager = new ViewManager();
            ViewManager.State = GameState.Menu;

            Players.Add(new Player(PlayerIdentity.PlayerLeft));
            Players.Add(new Player(PlayerIdentity.PlayerRight));

            base.Initialize();
        }

        /// <summary>
        /// LoadContent will be called once per game and is the place to load
        /// all of your content.
        /// </summary>
        protected override void LoadContent()
        {
            // Create a new SpriteBatch, which can be used to draw textures.
            spriteBatch = new SpriteBatch(GraphicsDevice);

            // TODO: use this.Content to load your game content here
            viewManager.LoadContent(this.Content);
        }

        /// <summary>
        /// UnloadContent will be called once per game and is the place to unload
        /// all content.
        /// </summary>
        protected override void UnloadContent()
        {
            // TODO: Unload any non ContentManager content here
        }

        /// <summary>
        /// Allows the game to run logic such as updating the world,
        /// checking for collisions, gathering input, and playing audio.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Update(GameTime gameTime)
        {
            // Allows the game to exit
            if ((GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed))
                this.Exit();

            // Put all other keyboard updates in their views, and not here

            // TODO: Add your update logic here
            viewManager.Update(gameTime);

            base.Update(gameTime);
        }

        /// <summary>
        /// This is called when the game should draw itself.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Draw(GameTime gameTime)
        {
            GraphicsDevice.Clear(Color.Black);

            // TODO: Add your drawing code here
            spriteBatch.Begin(SpriteSortMode.FrontToBack, null);
            viewManager.Draw(spriteBatch);
            spriteBatch.End();

            base.Draw(gameTime);
        }
    }
}
